Messages in this thread | | | Date | Thu, 8 Oct 2020 10:09:09 +0200 | From | Pavel Machek <> | Subject | Re: [PATCH v5 4/5] docs: counter: Document character device interface |
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Hi!
> + int main(void) > + { > + struct pollfd pfd = { .events = POLLIN }; > + struct counter_event event_data[2]; > + > + pfd.fd = open("/dev/counter0", O_RDWR); > + > + ioctl(pfd.fd, COUNTER_SET_WATCH_IOCTL, watches); > + ioctl(pfd.fd, COUNTER_SET_WATCH_IOCTL, watches + 1); > + ioctl(pfd.fd, COUNTER_LOAD_WATCHES_IOCTL); > + > + for (;;) { > + poll(&pfd, 1, -1);
Why do poll, when you are doing blocking read?
> + read(pfd.fd, event_data, sizeof(event_data));
Does your new chrdev always guarantee returning complete buffer?
If so, should it behave like that?
Best regards, Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html [unhandled content-type:application/pgp-signature] | |